summaryrefslogtreecommitdiff
path: root/otfl-font-cid.lua
blob: 7165288cfa1b907034a190832a10cc86d77803a4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
if not modules then modules = { } end modules ['font-cid'] = {
    version   = 1.001,
    comment   = "companion to font-otf.lua (cidmaps)",
    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
    copyright = "PRAGMA ADE / ConTeXt Development Team",
    license   = "see context related readme files"
}

local format, match, lower = string.format, string.match, string.lower
local tonumber = tonumber

local trace_loading = false  trackers.register("otf.loading",      function(v) trace_loading      = v end)

fonts         = fonts         or { }
fonts.cid     = fonts.cid     or { }
fonts.cid.map = fonts.cid.map or { }
fonts.cid.max = fonts.cid.max or 10


-- original string parser: 0.109, lpeg parser: 0.036 seconds for Adobe-CNS1-4.cidmap
--
-- 18964 18964 (leader)
-- 0 /.notdef
-- 1..95 0020
-- 99 3000

local number  = lpeg.C(lpeg.R("09","af","AF")^1)
local space   = lpeg.S(" \n\r\t")
local spaces  = space^0
local period  = lpeg.P(".")
local periods = period * period
local name    = lpeg.P("/") * lpeg.C((1-space)^1)

local unicodes, names = { }, { }

local function do_one(a,b)
    unicodes[tonumber(a)] = tonumber(b,16)
end

local function do_range(a,b,c)
    c = tonumber(c,16)
    for i=tonumber(a),tonumber(b) do
        unicodes[i] = c
        c = c + 1
    end
end

local function do_name(a,b)
    names[tonumber(a)] = b
end

local grammar = lpeg.P { "start",
    start  = number * spaces * number * lpeg.V("series"),
    series = (spaces * (lpeg.V("one") + lpeg.V("range") + lpeg.V("named")) )^1,
    one    = (number * spaces  * number) / do_one,
    range  = (number * periods * number * spaces * number) / do_range,
    named  = (number * spaces  * name) / do_name
}

function fonts.cid.load(filename)
    local data = io.loaddata(filename)
    if data then
        unicodes, names = { }, { }
        grammar:match(data)
        local supplement, registry, ordering = match(filename,"^(.-)%-(.-)%-()%.(.-)$")
        return {
            supplement = supplement,
            registry   = registry,
            ordering   = ordering,
            filename   = filename,
            unicodes   = unicodes,
            names      = names
        }
    else
        return nil
    end
end

local template = "%s-%s-%s.cidmap"

local function locate(registry,ordering,supplement)
    local filename = format(template,registry,ordering,supplement)
    local hashname = lower(filename)
    local cidmap = fonts.cid.map[hasnname]
    if not cidmap then
        if trace_loading then
            logs.report("load otf","checking cidmap, registry: %s, ordering: %s, supplement: %s, filename: %s",registry,ordering,supplement,filename)
        end
        local fullname = resolvers.find_file(filename,'cid') or ""
        if fullname ~= "" then
            cidmap = fonts.cid.load(fullname)
            if cidmap then
                if trace_loading then
                    logs.report("load otf","using cidmap file %s",filename)
                end
                fonts.cid.map[hashname] = cidmap
                cidmap.usedname = file.basename(filename)
                return cidmap
            end
        end
    end
    return cidmap
end

function fonts.cid.getmap(registry,ordering,supplement)
    -- cf Arthur R. we can safely scan upwards since cids are downward compatible
    local supplement = tonumber(supplement)
    if trace_loading then
        logs.report("load otf","needed cidmap, registry: %s, ordering: %s, supplement: %s",registry,ordering,supplement)
    end
    local cidmap = locate(registry,ordering,supplement)
    if not cidmap then
        local cidnum = nil
        -- next highest (alternatively we could start high)
        if supplement < fonts.cid.max then
            for supplement=supplement+1,fonts.cid.max do
                local c = locate(registry,ordering,supplement)
                if c then
                    cidmap, cidnum = c, supplement
                    break
                end
            end
        end
        -- next lowest (least worse fit)
        if not cidmap and supplement > 0 then
            for supplement=supplement-1,0,-1 do
                local c = locate(registry,ordering,supplement)
                if c then
                    cidmap, cidnum = c, supplement
                    break
                end
            end
        end
        -- prevent further lookups
        if cidmap and cidnum > 0 then
            for s=0,cidnum-1 do
                filename = format(template,registry,ordering,s)
                if not fonts.cid.map[filename] then
                    fonts.cid.map[filename] = cidmap -- copy of ref
                end
            end
        end
    end
    return cidmap
end